Answer:
(2.4, -1.2)
Step-by-step explanation:
Start by moving the x and the y to the same side and moving the number across the equal sign in both equations. We should now have y-0.45x=-2.3 and 2y+4.2x=7.8. We can use the elimination method by multiplying the first equation by -2 to get -2y+0.9x=4.6 and 2y+4.2x=7.8. From there, add the two equations together, eliminating y (-2+2=0). We now have 5.1x=12.4; divide both sides by 5.1 to get x=2.4. Then, in any of the two equations, let's use y-0.45x=-2.3, substitute x with 2.4. Now we have y-1.08=-2.3. Add 1.08 to both sides to get y=-1.22; round that to the nearest tenth to get -1.2.
Answer:420
Step-by-step explanation x=90/0.375
<span>Given:
xbar = 20 min
standard deviation = 8 min
total sample = 240
Required:
how many gym members are expected to spend 4 min and 36 min on a treadmill today
Solution:
sd</span>² = (∑(x - xbar)²) / N - 1
there are 42 gym members at 4 minutes and 200 gym members in 36 minutes.
Answer:
Ron has 15 nickels and 9 quarters
Step-by-step explanation:
Create a system of equations where n is the number of nickels and q is the number of quarters he has:
n + q = 24
0.05n + 0.25q = 3
Solve by elimination by multiplying the top equation by -0.25
-0.25n - 0.25q = -6
0.05n + 0.25q = 3
Add them together and solve for n:
-0.2n = -3
n = 15
So, Ron has 15 nickels. Find how many quarters he has by subtracting 15 from 24:
24 - 15
= 9
So, Ron has 15 nickels and 9 quarters.
